Electrochemically induced fractures in crystalline silicon anodes

Journal Article · Thu Apr 04 00:00:00 EDT 2019 · Journal of Power Sources

DOI:https://doi.org/10.1016/j.jpowsour.2019.03.105· OSTI ID:1509668

Yoon, Taeho ^[1]; Xiao, Chuanxiao ^[2]; Liu, Jun ^[2]; Wang, Yikai ^[3]; Son, Seoungbum ^[2]; Burrell, Anthony ^[2]; Ban, Chunmei ^[4]

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1. National Renewable Energy Lab. (NREL), Golden, CO (United States); Yeungnam Univ., Gyeongsan (Korea, Republic of)
2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
3. National Renewable Energy Lab. (NREL), Golden, CO (United States); Univ. of Kentucky, Lexington, KY (United States)
4. National Renewable Energy Lab. (NREL), Golden, CO (United States); Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)

This communication presents our recent discovery on electrochemically induced fracture behavior of a single-crystal silicon (Si) anode, with particular focus on the initialization and propagation of cracks. Intensive efforts have investigated mechanical properties and cracking behavior of Si electrodes overextended electrochemical cycles. However, it is still elusive how cracks nucleate and propagate in the crystalline Si anodes at the very early stage. Here, we examined the morphology evolution of the Si (100) wafer electrodes during the first electrochemical cycle, and we found that the formation of <110>-oriented buckles - induced by the anisotropic lithiation in crystalline Si during 1st lithiation - results in cracks propagated along the <110> direction in the buckled region during 1st delithiation. Surprisingly, as the delithiation proceeds, new cracks oriented along the <100> direction appear in the intact area where no macroscopic deformation occurred during the previous lithiation. The <100>-oriented cracks have not been studied previously. Herein, we introduce a linear elastic fracture mechanics model to help understand underlying mechanisms for such crack propagation. The findings in this work provide significant insights into the fracture behavior and formation mechanism, as well as possible strategies to inhibit crack propagations of Si electrodes at the beginning stage of cycling.

• Research Organization: National Renewable Energy Lab. (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V); USDOE
• Grant/Contract Number: AC36-08GO28308
• OSTI ID: 1509668
• Alternate ID(s): OSTI ID: 1547552
• Report Number(s): NREL/JA-5900-72932
• Journal Information: Journal of Power Sources, Vol. 425, Issue C; ISSN 0378-7753
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
fracture
silicon electrodes
lithium-ion batteries
buckling